Analysts George Cole, Robin Brooks and Michael Cahill, wrote: “A vote for the UK to exit from the EU is an event that would increase uncertainty, weigh on the UK outlook and raise concerns of foreign investors – potentially interrupting the flow of capital to the UK, sending the pound much lower.

“We can estimate the potential magnitude of a move [in sterling]. One way to do this is to assume that a ‘Brexit’ decision causes an interruption to capital flows into the UK that forces a sharp closure of the current account deficit, admittedly a strong assumption.”

They estimated this could lead to a short-term drop in trade-weighted sterling of 15-20%. This would take the pound down to $1.15-1.20 and the euro up to £0.90-0.95.

The Goldman team noted that the pound tumbled 20% on a trade-weighted basis during the global financial crisis between July 2008 and March 2009, and the current account deficit moved from 3.4% of GDP – similar to the current deficit – to virtually zero.

However, the analysts added that their forecasts are “based on a view that the UK will remain in the EU and that, as a result, the underlying dynamics will remain solid in the UK economy”. They continue to forecast the pound at $1.40 and the euro-sterling exchange at £0.68 in 12 months’ time.